1 | /* Tests for POSIX timer implementation using another process's CPU clock. */ |
2 | |
3 | #include <unistd.h> |
4 | |
5 | #if _POSIX_THREADS && defined _POSIX_CPUTIME |
6 | |
7 | #include <errno.h> |
8 | #include <stdio.h> |
9 | #include <stdlib.h> |
10 | #include <string.h> |
11 | #include <fcntl.h> |
12 | #include <time.h> |
13 | #include <signal.h> |
14 | #include <sys/wait.h> |
15 | |
16 | #include <support/xunistd.h> |
17 | |
18 | static clockid_t child_clock; |
19 | |
20 | #define TEST_CLOCK child_clock |
21 | #define TEST_CLOCK_MISSING(clock) \ |
22 | (setup_test () ? "other-process CPU clock timer support" : NULL) |
23 | |
24 | /* This function is intended to rack up both user and system time. */ |
25 | static void |
26 | chew_cpu (void) |
27 | { |
28 | while (1) |
29 | { |
30 | static volatile char buf[4096]; |
31 | for (int i = 0; i < 100; ++i) |
32 | for (size_t j = 0; j < sizeof buf; ++j) |
33 | buf[j] = 0xaa; |
34 | int nullfd = open (file: "/dev/null" , O_WRONLY); |
35 | for (int i = 0; i < 100; ++i) |
36 | for (size_t j = 0; j < sizeof buf; ++j) |
37 | buf[j] = 0xbb; |
38 | xwrite (nullfd, (char *) buf, sizeof buf); |
39 | close (fd: nullfd); |
40 | if (getppid () == 1) |
41 | _exit (2); |
42 | } |
43 | } |
44 | |
45 | static pid_t child; |
46 | static void |
47 | cleanup_child (void) |
48 | { |
49 | if (child <= 0) |
50 | return; |
51 | if (kill (pid: child, SIGKILL) < 0 && errno != ESRCH) |
52 | printf (format: "cannot kill child %d: %m\n" , child); |
53 | else |
54 | { |
55 | int status; |
56 | errno = 0; |
57 | if (waitpid (pid: child, stat_loc: &status, options: 0) != child) |
58 | printf (format: "waitpid %d: %m\n" , child); |
59 | } |
60 | } |
61 | #define CLEANUP_HANDLER cleanup_child () |
62 | |
63 | static int |
64 | setup_test (void) |
65 | { |
66 | /* Test timers on a process CPU clock by having a child process eating |
67 | CPU. First make sure we can make such timers at all. */ |
68 | |
69 | int pipefd[2]; |
70 | if (pipe (pipedes: pipefd) < 0) |
71 | { |
72 | printf (format: "pipe: %m\n" ); |
73 | exit (1); |
74 | } |
75 | |
76 | child = fork (); |
77 | |
78 | if (child == 0) |
79 | { |
80 | char c; |
81 | close (fd: pipefd[1]); |
82 | if (read (pipefd[0], &c, 1) == 1) |
83 | chew_cpu (); |
84 | _exit (1); |
85 | } |
86 | |
87 | if (child < 0) |
88 | { |
89 | printf (format: "fork: %m\n" ); |
90 | exit (1); |
91 | } |
92 | |
93 | atexit (func: &cleanup_child); |
94 | |
95 | close (fd: pipefd[0]); |
96 | |
97 | int e = clock_getcpuclockid (pid: child, clock_id: &child_clock); |
98 | if (e == EPERM) |
99 | { |
100 | puts (s: "clock_getcpuclockid does not support other processes" ); |
101 | return 1; |
102 | } |
103 | if (e != 0) |
104 | { |
105 | printf (format: "clock_getcpuclockid: %s\n" , strerror (errnum: e)); |
106 | exit (1); |
107 | } |
108 | |
109 | timer_t t; |
110 | if (timer_create (TEST_CLOCK, NULL, timerid: &t) != 0) |
111 | { |
112 | printf (format: "timer_create: %m\n" ); |
113 | return 1; |
114 | } |
115 | timer_delete (timerid: t); |
116 | |
117 | /* Get the child started chewing. */ |
118 | if (write (pipefd[1], "x" , 1) != 1) |
119 | { |
120 | printf (format: "write to pipe: %m\n" ); |
121 | return 1; |
122 | } |
123 | close (fd: pipefd[1]); |
124 | |
125 | return 0; |
126 | } |
127 | |
128 | #else |
129 | # define TEST_CLOCK_MISSING(clock) "process clocks" |
130 | #endif |
131 | |
132 | #include "tst-timer4.c" |
133 | |